Fluke 2620A, 2625A user manual Dedicated Alarm Output Test

Maintenance 6

Performance Tests

Hydra Series II’s display should now show the totalizing value incrementing at a 10 count per second rate.

Dedicated Alarm Output Test

The Dedicated Alarm Output Test verifies that Alarm Outputs 0 through 3 are functioning properly. Because this test is dependent on voltage readings the Accuracy Verification Test for channel 0 and the Channel Integrity Test for channels 1 through 3 should be performed if voltage readings are suspect.

1.Switch OFF power to the instrument and disconnect all high voltage inputs.

2.Remove the Alarm Output eight terminal connector module from the rear of Hydra Series II and all external connections to it. Connect short wires (to be used as test leads) to the ground (J) and 0 through 3 terminals. Leave other ends of wires unconnected at this time. Reinstall the connector.

3.Remove the Input Module from the rear of Hydra Series II. Open the Input Module and jumper the H (high) terminal of channels 1, 2, and 3 together. Connect a test lead to the H of channel 1. Also jumper the L (low) terminals of channel 1, 2, and 3 together. Connect a second test lead to the L of channel 1. Install the Input Module back into Hydra Series II. Refer to Figure 6-4.

4.Switch power ON.

5.Using a digital multimeter (DMM), verify that alarm outputs 0 through 3 are in the OFF or HIGH state. Perform this test by connecting the low or common of the multimeter to the ground test lead and the high of the multimeter to the alarm output. Verify a voltage greater than +3.8V dc.

6.Connect a cable from the Output VA HI and LO connectors of the 5700A to the VΩ

and COM connectors on the front panel of Hydra Series II. Then jumper Hydra Series II’s VΩ terminal to the H (high) test lead of the Input Module and the COM terminal to the L (low) test lead (See Input Connection diagram).

7.On Hydra Series II, select the VDC function, 3V range, and assign a HI alarm limit of +1.0000 for channels 0 through 3. Set up all other channels (4-20) to the OFF function. Select a scan interval of 5 seconds.

8.Set the 5700A to output +0.9900 volts.

9.Press Hydra Series II’s SCAN button. Hydra Series II should scan channels 0 through 3 every 5 seconds.

10.Using a digital multimeter, again verify that alarm outputs 0 through 3 are in the OFF or HIGH state.

11.Set the 5700A to output +1.1000 volts. Verify that the alarm outputs 0 through 3 are in the ON or LOW state (measure less than +0.8V dc).

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